Relaxation processes of some simple aliphatic molecules in dilute solutions

1977 ◽  
Vol 55 (4) ◽  
pp. 297-301 ◽  
Author(s):  
M. P. Madan
Keyword(s):  
Carbon Tetrachloride ◽  
Dielectric Relaxation ◽  
Thermodynamic Parameters ◽  
Relaxation Times ◽  
Relaxation Processes ◽  
Dilute Solutions ◽  
Microwave Region ◽  
Nonpolar Solvents ◽  
Dielectric Data ◽  
Intramolecular Rotation

The dielectric relaxation processes of acetone, cyclohexanone, 4-methyl-2-pentanone, and 4-heptanone in dilute nonpolar solvents, n-heptane, cyclohexane, benzene, and carbon tetrachloride have been studied in the microwave region over a temperature range 10 to 60 °C. The relaxation times and the thermodynamic parameters for the activated states have been determined using the measured dielectric data. The results have been discussed in terms of dipole reorientation by molecular and intramolecular rotation and compared, wherever possible, with other similar studies on aliphatic molecules.

Relaxation processes of quinoline, isoquinoline, and their mixtures

1980 ◽  
Vol 58 (1) ◽  
pp. 20-24 ◽  
Author(s):  
M. P. Madan
Keyword(s):  
Thermodynamic Parameters ◽  
Molecular Motion ◽  
Polar Solvent ◽  
Relaxation Times ◽  
Relaxation Processes ◽  
Polar Components ◽  
Dielectric Absorption ◽  
System A ◽  
Dielectric Data ◽  
Activated State

The dielectric absorption of quinoline, isoquinoline, and their binary mixtures has been studied in the microwave region over a range of temperatures in dilute benzene and n-heptane solutions. The relaxation times and the thermodynamic parameters for the activated state have been determined using the measured dielectric data. The results obtained have been discussed in terms of the molecular motion of the system. A relation has been proposed to represent the relaxation behavior of a system of two Debye-type polar components in a non-polar solvent. The relation has been tested by comparing the calculated values with those determined experimentally for a few systems consisting of similar, simple rigid polar molecules.

The dielectric behaviour of dipolar mixtures I: chlorobenzene–nitrobenzene mixtures

1986 ◽  
Vol 64 (11) ◽  
pp. 1534-1536 ◽  
Author(s):  
F. F. Hanna ◽  
K. N. Abdel-Nour ◽  
A. M. Ghoneim
Keyword(s):  
Relaxation Time ◽  
Thermodynamic Parameters ◽  
Relaxation Times ◽  
Dielectric Behaviour ◽  
Dilute Solutions ◽  
Single Relaxation Time ◽  
Microwave Region ◽  
Dielectric Absorption

The dielectric absorption of dilute solutions of nitrobenzene, chlorobenzene, and their mixtures in cyclohexane and Decalin® have been measured in the microwave region at three temperatures between 20 and 40 °C. The relaxation times and thermodynamic parameters are determined. A single relaxation time is found for the mixtures, and the results are discussed.

Dielectric relaxation of some aliphatic ester molecules in solutions

1979 ◽  
Vol 57 (7) ◽  
pp. 1035-1038 ◽  
Author(s):  
M. P. Madan
Keyword(s):  
Relaxation Time ◽  
Dielectric Relaxation ◽  
Relaxation Times ◽  
Activation Parameters ◽  
Dielectric Absorption ◽  
Aliphatic Ketones ◽  
Dielectric Data ◽  
Aliphatic Ester ◽  
Aliphatic Esters ◽  
Intramolecular Rotation

The dielectric absorption of several aliphatic esters has been examined in the microwave region over a range of temperatures in n-heptane, cyclohexane, and benzene. The relaxation times and the thermodynamic parameters have been determined using the measured dielectric data. The values of the relaxation time for those solutions for which there are available known data agree well with other determinations. The relaxation times and the various molar activation parameters have been discussed in terms of dipole reorientation by molecular and intramolecular rotation. It would appear that the relaxation behavior of aliphatic esters is similar to that for other aliphatic molecules, such as aliphatic ketones studied previously.

Microwave Absorption and Relaxation Behavior of Some Simple Ketones in Dilute Solutions

1975 ◽  
Vol 53 (1) ◽  
pp. 23-28 ◽  
Author(s):  
M. P. Madan
Keyword(s):  
Relaxation Time ◽  
Thermodynamic Parameters ◽  
Microwave Absorption ◽  
Reasonable Agreement ◽  
Relaxation Times ◽  
Relaxation Behavior ◽  
The Other ◽  
Dielectric Absorption ◽  
Dielectric Data ◽  
Thermodynamic Processes

The dielectric absorption of solutions of 2-hexanone, 4- and 5-nonanone, and 2-decanone has been examined in the microwave region over a range of temperatures in n-heptane, cyclohexane, and benzene. The relaxation times and the thermodynamic parameters for the activated states have been determined using the measured dielectric data. The values of relaxation time are in reasonable agreement at the temperature at which there are available known data. Both the relaxation behavior and the thermodynamic processes are discussed and, where possible, compared with corresponding results of the other workers.

scholarly journals Квазистационарные процессы диэлектрической релаксации в тонких поликристаллических пленках PZT

2020 ◽  
Vol 62 (10) ◽  
pp. 1665
Author(s):  
В.В. Иванов ◽  
Е.Н. Голубева ◽  
О.Н. Сергеева ◽  
Г.М. Некрасова ◽  
И.П. Пронин ◽  
...  
Keyword(s):  
Electric Field ◽  
Dielectric Relaxation ◽  
External Electric Field ◽  
Annealing Temperature ◽  
Relaxation Times ◽  
Polarization Vector ◽  
Silicon Substrates ◽  
Relaxation Processes ◽  
Pzt Films

In this work, relaxation processes in polycrystalline PZT films formed on silicon substrates with a quasistatic change in the external electric field are studied. It is shown that dielectric relaxation is characterized by at least three relaxation times, which depend on the direction of self-polarization vector in the film, the magnitude of the polarizing field, and also on the annealing temperature of the PZT films.

Dielectric relaxation of nitromethane, some nitriles, and their mixtures in dilute solutions

1987 ◽  
Vol 65 (12) ◽  
pp. 1573-1576 ◽  
Author(s):  
M. P. Madan
Keyword(s):  
Refractive Index ◽  
Dielectric Relaxation ◽  
Thermodynamic Parameters ◽  
Molecular Motion ◽  
Empirical Relation ◽  
Relaxation Times ◽  
Relaxation Behaviour ◽  
Polar Components ◽  
Dielectric Absorption ◽  
Activated State

The dielectric absorption of nitromethane, benzonitrile, and acetonitrile and their binary mixtures has been studied in the microwave region over a range of temperatures in dilute benzene solutions. The data on static and optical permittivities at 20 °C have also been obtained, from measurements at 100 kHz and from measuring the refractive index for sodium-D lines, for a few cases. These data have been used to determine the relaxation times and the thermodynamic parameters for the activated state. The results obtained have been discussed in terms of the molecular motion of the systems. A new empirical relation has been proposed to represent the relaxation behaviour of a system of two Debye-type polar components in a nonpolar solvent. The relation has been tested, along with a previously suggested relation, by comparing the calculated values with those determined experimentally.

Dielectric relaxation processes of some dialkyl disulfides

1983 ◽  
Vol 61 (9) ◽  
pp. 2107-2111 ◽  
Author(s):  
H. A. Khwaja ◽  
S. Walker
Keyword(s):  
Dielectric Relaxation ◽  
Relaxation Processes ◽  
Alkyl Chains ◽  
Polystyrene Matrix ◽  
Segmental Relaxation ◽  
Higher Temperature ◽  
Dialkyl Disulfides ◽  
Intramolecular Rotation ◽  
Two Temperature ◽  
Low Temperature Process

Dielectric relaxation studies have been performed for dimethyl, diethyl, di-isopropyl, di-n-butyl, di-tert-butyl, and di-n-octyl disulfides in a polystyrene matrix. For the last five compounds the absorption appears in two temperature regions. The relaxation data for the higher temperature regions are consistent with intramolecular rotation around the S—S bond with accompanying flexibility in the alkyl chains. The enthalpy barrier to this relaxation process is ~29 kJ mol−1 and is the trans (lower) barrier. This value is typical for all six dialkyl disulfides. The most likely interpretation of the low temperature process is that there is segmental relaxation of the alkyl chains which also involves movement of the main dipoles (S—S and S—C).

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